Language and Mind

Linguistic Contributions to the Study of Mind (Future)

Source: Language and Mind publ. Harcourt Brace Jovanovich, Inc., 1968. One of the six lectures is reproduced here.

In discussing the past, I referred to two major traditions that
have enriched the study of language in their separate and very
different ways; and in my last lecture, I tried to give some indication
of the topics that seem on the immediate horizon today, as a kind
of synthesis of philosophical grammar and structural linguistics
begins to take shape. Each of the major traditions of study and
speculation that I have been using as a point of reference was
associated with a certain characteristic approach to the problems
of mind; we might say, without distortion, that each evolved as
a specific branch of the psychology of its time, to which it made
a distinctive contribution.

It may seem a bit paradoxical to speak of structural linguistics
in this way, given its militant anti-psychologism. But the paradox
is lessened when we take note of the fact that this militant anti-psychologism
is no less true of much of contemporary psychology itself, particularly
of those branches that until a few years ago monopolised the study
of use and acquisition of language. We live, after all, in the
age of "behavioural science," not of "the science
of mind." I do not want to read too much into a terminological
innovation, but I think that there is some significance in the
ease and willingness with which modern thinking about man and
society accepts the designation "behavioural science."
No sane person has ever doubted that behaviour provides much of
the evidence for this study — all of the evidence, if we interpret
"behaviour" in a sufficiently loose sense. But the
term "behavioural science" suggests a not-so-subtle
shift of emphasis toward the evidence itself and away from the
deeper underlying principles and abstract mental structures that
might be illuminated by the evidence of behaviour. It is as if
natural science were to be designated "the science of meter
readings." What, in fact, would we expect of natural science
in a culture that was satisfied to accept this designation for
its activities?

Behavioural science has been much preoccupied with data and organisation
of data, and it has even seen itself as a kind of technology of
control of behaviour. Anti-mentalism in linguistics and in philosophy
of language conforms to this shift of orientation. As I mentioned
in my first lecture, I think that one major indirect contribution
of modern structural linguistics results from its success in making
explicit the assumptions of an anti-mentalistic, thoroughly operational
and behaviourist approach to the phenomena of language. By extending
this approach to its natural limits, it laid the groundwork for
a fairly conclusive demonstration of the inadequacy of any such
approach to the problems of mind.

More generally, I think that the long-range significance of the
study of language lies in the fact that in this study it is possible
to give a relatively sharp and clear formulation of some of the
central questions of psychology and to bring a mass of evidence
to bear on them. What is more, the study of language is, for
the moment, unique in the combination it affords of richness of
data and susceptibility to sharp formulation of basic issues.

It would, of course, be silly to try to predict the future of
research, and it will be understood that I do not intend the subtitle
of this lecture to be taken very seriously. Nevertheless, it
is fair to suppose that the major contribution of the study of
language will lie in the understanding it can provide as to the
character of mental processes and the structures they form and
manipulate. Therefore, instead of speculating on the likely course
of research into the problems that are coming into focus today,
I will concentrate here on some of the issues that arise when
we try to develop the study of linguistic structure as a chapter
of human psychology.

It is quite natural to expect that a concern for language will
remain central to the study of human nature, as it has been in
the past. Anyone concerned with the study of human nature and
human capacities must somehow come to grips with the fact that
all normal humans acquire language, whereas acquisition of even
its barest rudiments is quite beyond the capacities of an otherwise
intelligent ape a fact that was emphasised, quite correctly, in
Cartesian philosophy.' It is widely thought that the extensive
modern studies of animal communication challenge this classical
view; and it is almost universally taken for granted that there
exists a problem of explaining the "evolution" of human
language from systems of animal communication. However, a careful
look at recent studies of animal communication seems to me to
provide little support for these assumptions. Rather, these studies
simply bring out even more clearly the extent to which human language
appears to be a unique phenomenon, without significant analogue
in the animal world. If this is so, it is quite senseless to
raise the problem of explaining the evolution of human language
from more primitive systems of communication that appear at lower
levels of intellectual capacity. The issue is important, and
I would like to dwell on it for a moment.

The assumption that human language evolved from more primitive
systems is developed in an interesting way by Karl Popper in his
recently published Arthur Compton Lecture, "Clouds and Clocks."
He tries to show how problems of freedom of will and Cartesian
dualism can be solved by the analysis of this "evolution."
I am not concerned now with the philosophical conclusions that
he draws from this analysis, but with the basic assumption that
there is an evolutionary development of language from simpler
systems of the sort that one discovers in other organisms. Popper
argues that the evolution of language passed through several stages,
in particular a "lower stage" in which vocal gestures
are used for expression of emotional state, for example, and a
"higher stage" in which articulated sound is used for
expression of thought — in Popper's terms, for description and critical
argument. His discussion of stages of evolution of language suggests
a kind of continuity, but in fact he establishes no relation between
the lower and higher stages and does not suggest a mechanism whereby
transition can take place from one stage to the next. In short,
he gives no argument to show that the stages belong to a single
evolutionary process. In fact, it is difficult to see what links
these stages at all (except for the metaphorical use of the term
"language"). There is no reason to suppose that the
"gaps" are bridgeable. There is no more of a basis
for assuming an evolutionary development of "higher"
from "lower" stages, in this case, than there is for
assuming an evolutionary development from breathing to walking;
the stages have no significant analogy, it appears, and seem to
involve entirely different processes and principles.

A more explicit discussion of the relation between human language
and animal communication systems appears in a recent discussion
by the comparative ethologist W. H. Thorpe. He points out that
mammals other than man appear to lack the human ability to imitate
sounds, and that one might therefore have expected birds (many
of which have this ability to a remarkable extent) to be "the
group which ought to have been able to evolve language in the
true sense, and not the mammals." Thorpe does not suggest
that human language "evolved" in any strict sense from
simpler systems, but he does argue that the characteristic properties
of human language can be found in animal communication systems,
although "we cannot at the moment say definitely that they
are all present in one particular animal." The characteristics
shared by human and animal language are the properties of being
"purposive," "syntactic," and "propositional."
Language is purposive "in that there is nearly always in
human speech a definite intention of getting something over to
somebody else, altering his behaviour, his thoughts, or his general
attitude toward a situation." Human language is "Syntactic"
in that an utterance is a performance with an internal organisation,
with structure and coherence. It is "propositional"
in that it transmits information. In this sense, then, both human
language and animal communication are purposive, syntactic, and
propositional.

All this may be true, but it establishes very little, since when
we move to the level of abstraction at which human language and
animal communication fall together, almost all other behaviour
is included as well. Consider walking: Clearly, walking is purposive
behaviour, in the most general sense of "purposive."
Walking is also "syntactic" in the
sense just defined, as, in fact, Karl Lashley pointed out a long
time ago in his important discussion of serial order in behaviour,
to which I referred in the first lecture. Furthermore, it can
certainly be informative; for example, I can signal my interest in reaching a certain goal
by the speed or intensity with which I walk.

It is, incidentally, precisely in this manner that the examples
of animal communication that Thorpe presents are "propositional."
He cites as an example the song of the European robin, in which
the rate of alternation of high and low pitch signals the intention
of the bird to defend its territory; the higher the rate of alternation,
the greater the intention to defend the territory. The example
is interesting, but it seems to me to show very clearly the hopelessness
of the attempt to relate human language to animal communication.
Every animal communication system that is known (if we disregard
some science fiction about dolphins) uses one of two basic principles:
Either it consists of a fixed, finite number of signals, each
associated with a specific range of behaviour or emotional state,
as is illustrated in the extensive primate studies that have been
carried out by Japanese scientists for the past several years;
or it makes use of a fixed, finite number of linguistic dimensions,
each of which is associated with a particular nonlinguistic dimension
in such a way that selection of a point along the linguistic dimension
determines and signals a certain point along the associated nonlinguistic
dimension. The latter is the principle realised in Thorpe's bird-song
example. Rate of alternation of high and low pitch is a linguistic
dimension correlated with the nonlinguistic dimension of intention
to defend a territory. The bird signals its intention to defend
a territory by selecting a correlated point along the linguistic
dimension of pitch alternation — I use the word "select"
loosely, of course. The linguistic dimension is abstract, but
the principle is clear. A communication system of the second
type has an indefinitely large range of potential signals, as
does human language. The mechanism and principle, however, are
entirely different from those employed by human language to express
indefinitely many new thoughts, intentions, feelings, and so on.
It is not correct to speak of a "deficiency" of the
animal system, in terms of range of potential signals; rather
the opposite, since the animal system admits in principle of continuous
variation along the linguistic dimension (insofar as it makes
sense to speak of "continuity" in such a case), whereas
human language is discrete. Hence, the issue is not one of "more"
or "less," but rather of an entirely different principle
of organisation. When I make some arbitrary statement in a human
language — say, that "the rise of supranational corporations
poses new dangers for human freedom" — I am not selecting a
point along some linguistic dimension that signals a corresponding
point along an associated nonlinguistic dimension, nor am I selecting
a signal from a finite behavioural repertoire, innate or learned.

Furthermore, it is wrong to think of human use of language as
characteristically informative, in fact or in intention. Human
language can be used to inform or mislead, to clarify one's own
thoughts or to display one's cleverness, or simply for play.
If I speak with no concern for modifying your behaviour or thoughts,
I am not using language any less than if I say exactly the same
things with such intention. If we hope to understand human language
and the psychological capacities on which it rests, we must first
ask what it is, not how or for what purposes it is used. When
we ask what human language is, we find no striking similarity
to animal communication systems. There is nothing useful to be
said about behaviour or thought at the level of abstraction at
which animal and human communication fall together. The examples
of animal communication that have been examined to date do share
many of the properties of human gestural systems, and it might
be reasonable to explore the possibility of direct connection
in this case. But human language, it appears, is based on entirely
different principles. This, I think, is an important point, often
overlooked by those who approach human language as a natural,
biological phenomenon; in particular, it seems rather pointless,
for these reasons, to speculate about the evolution of human language
from simpler systems — perhaps as absurd as it would be to speculate
about the "evolution" of atoms from clouds of elementary
particles.

As far as we know, possession of human language is associated
with a specific type of mental organisation, not simply a higher
degree of intelligence. There seems to be no substance to the
view that human language is simply a more complex instance of
something to be found elsewhere in the animal world. This poses
a problem for the biologist, since, if true, it is an example
of true "emergence" — the appearance of a qualitatively
different phenomenon at a specific stage of complexity of organisation.
Recognition of this fact, though formulated in entirely different
terms, is what motivated much of the classical study of language
by those whose primary concern was the nature of mind. And it
seems to me that today there is no better or more promising way
to explore the essential and distinctive properties of human intelligence
than through the detailed investigation of the structure of this
unique human possession. A reasonable guess, then, is that if
empirically adequate generative grammars can be constructed and
the universal principles that govern their structure and organisation
determined, then this will be an important contribution to human
psychology, in ways to which I will turn directly, in detail.

In the course of these lectures I have mentioned some of the classical
ideas regarding language structure and contemporary efforts to
deepen and extend them. It seems clear that we must regard linguistic
competence — knowledge of a language — as an abstract system underlying
behaviour, a system constituted by rules that interact to determine
the form and intrinsic meaning of a potentially infinite number
of sentences. Such a system — a generative grammar — provides an
explication of the Humboldtian idea of "form of language,"
which in an obscure but suggestive remark in his great posthumous
work, Über die Verschiedenheitdes Menschlichen
Sprachbaues, Humboldt defines as "that constant and unvarying
system of processes underlying the mental act of raising articulated
structurally organised signals to an expression of thought."
Such a grammar defines a language in the Humboldtian sense, namely
as "a recursively generated system, where the laws of generation
are fixed and invariant, but the scope and the specific manner
in which they are applied remain entirely unspecified."

In each such grammar there are particular, idiosyncratic elements,
selection of which ' determines one specific human language; and
there are general universal elements, conditions on the form and
organisation of any human language, that form the subject matter
for the study of "universal grammar." Among the principles
of universal grammar are those I discussed in the preceding lecture — for
example, the principles that distinguish deep and surface structure
and that constrain the class of transformational operations that
relate them. Notice, incidentally, that the existence of definite
principles of universal grammar makes possible the rise of the
new field of mathematical linguistics, a field that submits to
abstract study the class of generative systems meeting the conditions
set forth in universal grammar. This inquiry aims to elaborate
the formal properties of any possible human language. The field
is in its infancy; it is only in the last decade that the possibility
of such an enterprise has been envisioned. It has some promising
initial results, and it suggests one possible direction for future
research that might prove to be of great importance. Thus, mathematical
linguistics seems for the moment to be in a uniquely favourable
position, among mathematical approaches in the social and psychological
sciences, to develop not simply as a theory of data, but as the
study of highly abstract principles and structures that determine
the character of human mental processes. In this case, the mental
processes in question are those involved in the organisation of
one specific domain of human knowledge, namely knowledge of language.

The theory of generative grammar, both particular and universal,
points to a conceptual lacuna in psychological theory that I believe
is worth mentioning. Psychology conceived as "behavioural
science" has been concerned with behaviour and acquisition
or control of behaviour. It has no concept corresponding to "competence,"
in the sense in which competence is characterised by a generative
grammar. The theory of learning has limited itself to a narrow
and surely inadequate concept of what is learned — namely a system
of stimulus-response connections, a network of associations, a
repertoire of behavioural items, a habit hierarchy, or a system
of dispositions to respond in a particular way under specifiable
stimulus conditions.' Insofar as behavioural psychology has been
applied to education or therapy, it has correspondingly limited
itself to this concept of "what is learned." But a generative
grammar cannot be characterised in these terms. What is necessary,
in addition to the concept of behaviour and learning, is a concept
of what is learned — a notion of competence — that lies beyond the
conceptual limits of behaviourist psychological theory. Like
much of modern linguistics and modern philosophy of language,
behaviourist psychology has quite consciously accepted methodological
restrictions that do not permit the study of systems of the necessary
complexity and abstractness.' One important future contribution
of the study of language to general psychology may be to focus
attention on this conceptual gap and to demonstrate how it may
be filled by the elaboration of a system of underlying competence
in one domain of human intelligence.

There is an obvious sense in which any aspect of psychology is
based ultimately on the observation of behaviour. But it is not
at all obvious that the study of learning should proceed directly
to the investigation of factors that control behaviour or of conditions
under which a "behavioural repertoire" is established.
It is first necessary to determine the significant characteristics
of this behavioural repertoire, the principles on which it is
organised. A meaningful study of learning can proceed only after
this preliminary task has been carried out and has led to a reasonably
well-confirmed theory of underlying competence — in the case of
language, to the formulation of the generative grammar that underlies
the observed use of language. Such a study will concern itself
with the relation between the data available to the organism and
the competence that it acquires; only to the extent that the abstraction
to competence has been successful — in the case of language, to
the extent that the postulated grammar is "descriptively
adequate" in the sense described in Lecture 2 — can the investigation
of learning hope to achieve meaningful results. If, in some domain,
the organisation of the behavioural repertoire is quite trivial
and elementary, then there will be little harm in avoiding the
intermediate stage of theory construction, in which we attempt
to characterise accurately the competence that is acquired. But
one cannot count on this being the case, and in the study of language
it surely is not the case. With a richer and more adequate characterisation
of "what is learned" — of the underlying competence that
constitutes the "final state" of the organism being
studied — it may be possible to approach the task of constructing
a theory of learning that will be much less restricted in scope
than modern behavioural psychology has proved to be. Surely it
is pointless to accept methodological strictures that preclude
such an approach to problems of learning.

Are there other areas of human competence where one might hope
to develop a fruitful theory, analogous to generative grammar?
Although this is a very important question, there is very little
that can be said about it today. One might, for example, consider
the problem of how a person comes to acquire a certain concept
of three-dimensional space, or an implicit "theory of human
action," in similar terms. Such a study would begin with
the attempt to characterise the implicit theory that underlies
actual performance and would then turn to the question of how
this theory develops under the given conditions of time and access
to data that is, in what way the resulting system of beliefs is
determined by the interplay of available data, "heuristic
procedures," and the innate schematism that restricts and
conditions the form of the acquired system. At the moment, this
is nothing more than a sketch of a program of research.

There have been some attempts to study the structure of other,
language-like systems — the study of kinship systems and folk taxonomies
comes to mind, for example. But so far, at least, nothing has
been discovered that is even roughly comparable to language in
these domains. No one, to my knowledge, has devoted more thought
to this problem than Lévi-Strauss. For example, his recent
book on the categories of primitive mentality is a serious and
thoughtful attempt to come to grips with this problem. Nevertheless,
I do not see what conclusions can be reached from a study of his
materials beyond the fact that the savage mind attempts to impose
some organisation on the physical world — that humans classify,
if they perform any mental acts at all. Specifically, Lévi-Strauss's
well-known critique of totemism seems to reduce to little more
than this conclusion.

Lévi-Strauss models his investigations quite consciously
on structural linguistics, particularly on the work of Troubetzkoy
and Jakobson. He repeatedly and quite correctly emphasises that
one cannot simply apply procedures analogous to those of phonemic
analysis to subsystems of society and culture. Rather, he is
concerned with structures "where they may be found ... in
the kinship system, political ideology, mythology, ritual, art,"
and so on, and he wishes to examine the formal properties of
these structures in their own terms. But several reservations
are necessary when structural linguistics is used as a model
in this way. For one thing, the structure of a phonological system
is of very little interest as a formal object; there is nothing
of significance to be said, from a formal point of view, about
a set of forty-odd elements cross-classified in terms of eight
or ten features. The significance of structuralist phonology,
as developed by Troubetzkoy, Jakobson, and others, lies not in
the formal properties of phonemic systems but in the fact that
a fairly small number of features that can be specified in absolute,
language — independent terms appear to provide the basis for the
organisation of all phonological systems. The achievement of
structuralist phonology was to show that the phonological rules
of a great variety of languages apply to classes of elements that
can be simply characterised in terms of these features; that historical
change affects such classes in a uniform way; and that the organisation
of features plays a basic role in the use and acquisition of language.
This was a discovery of the greatest importance, and it provides
the groundwork for much of contemporary linguistics. But if we
abstract away from the specific universal set of features and
the rule systems in which they function, little of any significance
remains.

Furthermore, to a greater and greater extent, current work in
phonology is demonstrating that the real richness of phonological
systems lies not in the structural patterns of phonemes but rather
in the intricate systems of rules by which these patterns are
formed, modified, and elaborated.' The structural patterns that
arise at various stages of derivation are a kind of epiphenomenon.
The system of phonological rules makes use of the universal features
in a fundamental way, but it is the properties of the systems
of rules, it seems to me, that really shed light on the specific
nature of the organisation of language. For example, there appear
to be very general conditions, such as the principle of cyclic
ordering (discussed in the preceding lecture) and others that
are still more abstract, that govern the application of these
rules, and there are many interesting and unsolved questions as
to how the choice of rules is determined by intrinsic, universal
relations among features. Furthermore, the idea of a mathematical
investigation of language structures, to which Lévi-Strauss
occasionally alludes, becomes meaningful only when one considers
systems of rules with infinite generative capacity. There is
nothing to be said about the abstract structure of the various
patterns that appear at various stages of derivation. If this
is correct, then one cannot expect structuralist phonology, in
itself, to provide a useful model for investigation of other cultural
and social systems.

In general, the problem of extending concepts of linguistic structure
to other cognitive systems seems to me, for the moment, in not
too promising a state, although it is no doubt too early for pessimism.

Before turning to the general implications of the study of linguistic
competence and, more specifically, to the conclusions of universal
grammar, it is well to make sure of the status of these conclusions
in the light of current knowledge of the possible diversity of
language. In my first lecture, I quoted the remarks of William
Dwight Whitney about what he referred to as "the infinite
diversity of human speech," the boundless variety that, he
maintained, undermines the claims of philosophical grammar to
psychological relevance.

Philosophical grammarians had typically maintained that languages
vary little in their deep structures, though there may be wide
variability in surface manifestations. Thus there is, in this
view, an underlying structure of grammatical relations and categories,
and certain aspects of human thought and mentality are essentially
invariant across languages, although languages may differ as to
whether they express the grammatical relations formally by inflection
or word order, for example. Furthermore, an investigation of
their work indicates that the underlying recursive principles
that generate deep structure were assumed to be restricted in
certain ways — for example, by the condition that new structures
are formed only by the insertion of new "propositional content,"
new structures that themselves correspond to actual simple sentences,
in fixed positions in already formed structures. Similarly, the
grammatical transformations that form surface structures through
reordering, ellipsis, and other formal operations must themselves
meet certain fixed general conditions, such as those discussed
in the preceding lecture. In short, the theories of philosophical
grammar, and the more recent elaborations of these theories, make
the assumption that languages will differ very little, despite
considerable diversity in superficial realisation, when we discover
their deeper structures and unearth their fundamental mechanisms
and principles.

It is interesting to observe that this assumption persisted even
through the period of German romanticism, which was, of course,
much preoccupied with the diversity of cultures and with the many
rich possibilities for human intellectual development. Thus,
Wilhelm von Humboldt, who is now best remembered for his ideas
concerning the variety of languages and the association of diverse
language structures with divergent "world-views," nevertheless
held firmly that underlying any human language we will find a
system that is universal, that simply expresses man's unique intellectual
attributes. For this reason, it was possible for him to maintain
the rationalist view that language is not really learned — certainly
not taught — but rather develops "from within," in an
essentially predetermined way, when the appropriate environmental
conditions exist. One cannot really teach a first language, he
argued, but can only "provide the thread along which it will
develop of its own accord," by processes more like maturation
than learning. This Platonistic element in Humboldt's thought
is a pervasive one; for Humboldt, it was as natural to propose
an essentially Platonistic theory of "learning" as it
was for Rousseau to found his critique of repressive social institutions
on a conception of human freedom that derives from strictly Cartesian
assumptions regarding the limitations of mechanical explanation.
And in general it seems appropriate to construe both the psychology
and the linguistics of the romantic period as in large part a
natural outgrowth of rationalist conceptions."

The issue raised by Whitney against Humboldt and philosophical
grammar in general is of great significance with respect to the
implications of linguistics for general human psychology. Evidently,
these implications can be truly far-reaching only if the rationalist
view is essentially correct, in which case the structure of language
can truly serve as a "mirror of mind," in both its particular
and its universal aspects. It is widely believed that modern
anthropology has established the falsity of the assumptions of
the rationalist universal grammarians by demonstrating through
empirical study that languages may, in fact, exhibit the widest
diversity. Whitney's claims regarding the diversity of languages
are reiterated throughout the modern period; Martin Joos, for
example, is simply expressing the conventional wisdom when he
takes the basic conclusion of modern anthropological linguistics
to be that "languages can differ without limit as to either
extent or direction."

The belief that anthropological linguistics has demolished the
assumptions of universal grammar seems to me to be quite false
in two important respects. First, it misinterprets the views
of classical rationalist grammar, which held that languages are
similar only at the deeper level, the level at which grammatical
relations are expressed and at which the processes that provide
for the creative aspect of language use are to be found. Second,
this belief seriously misinterprets the findings of anthropological
linguistics, which has, in fact, restricted itself almost completely
to fairly superficial aspects of language structure.

To say this is not to criticise anthropological linguistics, a
field that is faced with compelling problems of its own — in particular,
the problem of obtaining at least some record of the rapidly vanishing
languages of the primitive world. Nevertheless, it is important
to bear in mind this fundamental limitation on its achievements
in considering the light it can shed on the theses of universal
grammar. Anthropological studies (like structural linguistic
studies in general) do not attempt to reveal the underlying core
of generative processes in language — that is, the processes that
determine the deeper levels of structure and that constitute the
systematic means for creating ever novel sentence types. Therefore,
they obviously cannot have any real bearing on the classical assumption
that these underlying generative processes vary only slightly
from language to language. In fact, what evidence is now available
suggests that if universal grammar has serious defects, as indeed
it does from a modern point of view, then these defects lie in
the failure to recognise the abstract nature of linguistic structure
and to impose sufficiently strong and restrictive conditions on
the form of any human language. And a characteristic feature
of current work in linguistics is its concern for linguistic universals
of a sort that can only be detected through a detailed investigation
of particular languages, universals governing properties of language
that are simply not accessible to investigation within the restricted
framework that has been adopted, often for very good reasons,
within anthropological linguistics.

I think that if we contemplate the classical problem of psychology,
that of accounting for human knowledge, we cannot avoid being
struck by the enormous disparity between knowledge and experience — in
the case of language, between the generative grammar that expresses
the linguistic competence of the native speaker and the meagre
and degenerate data on the basis of which he has constructed this
grammar for himself. In principle the theory of learning should
deal with this problem; but in fact it bypasses the problem, because
of the conceptual gap that I mentioned earlier. The problem cannot
even be formulated in any sensible way until we develop the concept
of competence, alongside the concepts of learning and behaviour,
and apply this concept in some domain. The fact is that this
concept has so far been extensively developed and applied only
in the study of human language. It is only in this domain that
we have at least the first steps toward an account of competence,
namely the fragmentary generative grammars that have been constructed
for particular languages. As the study of language progresses,
we can expect with some confidence that these grammars will be
extended in scope and depth, although it will hardly come as a
surprise if the first proposals are found to be mistaken in fundamental
ways.

Insofar as we have a tentative first approximation to a generative
grammar for some language, we can for the first time formulate
in a useful way the problem of origin of knowledge. In other
words, we can ask the question, What initial structure must be
attributed to the mind that enables it to construct such a grammar
from the data of sense? Some of the empirical conditions that
must be met by any such assumption about innate structure are
moderately clear. Thus, it appears to be a species-specific capacity
that is essentially independent of intelligence, and we can make
a fairly good estimate of the amount of data that is necessary
for the task to be successfully accomplished. We know that the
grammars that are in fact constructed vary only slightly among
speakers of the same language, despite wide variations not only
in intelligence but also in the conditions under which language
is acquired. As participants in a certain culture, we are naturally
aware of the great differences in ability to use language, in
knowledge of vocabulary, and so on that result from differences
in native ability and from differences in conditions of acquisition;
we naturally pay much less attention to the similarities and to
common knowledge, which we take for granted. But if we manage
to establish the requisite psychic distance, if we actually compare
the generative grammars that must be postulated for different
speakers of the same language, we find that the similarities that
we take for granted are quite marked and that the divergences
are few and marginal. What is more, it seems that dialects that
are superficially quite remote, even barely intelligible on first
contact, share a vast central core of common rules and processes
and differ very slightly in underlying structures, which seem
to remain invariant through long historical eras. Furthermore,
we discover a substantial system of principles that do not vary
among languages that are, as far as we know, entirely unrelated.

The central problems in this domain are empirical ones that are,
in principle at least, quite straightforward, difficult as they
may be to solve in a satisfactory way. We must postulate an innate
structure that is rich enough to account for the disparity between
experience and knowledge, one that can account for the construction
of the empirically justified generative grammars within the given
limitations of time and access to data. At the same time, this
postulated innate mental structure must not be so rich and restrictive
as to exclude certain known languages. There is, in other words,
an upper bound and a lower bound on the degree and exact character
of the complexity that can be postulated as innate mental structure.
The factual situation is obscure enough to leave room for much
difference of opinion over the true nature of this innate mental
structure that makes acquisition of language possible. However,
there seems to me to be no doubt that this is an empirical issue,
one that can be resolved by proceeding along the lines that I
have just roughly outlined.

My own estimate of the situation is that the real problem for
tomorrow is that of discovering an assumption regarding innate
structure that is sufficiently rich, not that of finding one that
is simple or elementary enough to be "plausible." There
is, as far as I can see, no reasonable notion of "plausibility,"
no a priori insight into what innate structures are permissible,
that can guide the search for a "sufficiently elementary
assumption." It would be mere dogmatism to maintain without
argument or evidence that the mind is simpler in its innate structure
than other biological systems, just as it would be mere dogmatism
to insist that the mind's organisation must necessarily follow
certain set principles, determined in advance of investigation
and maintained in defiance of any empirical findings. I think
that the study of problems of mind has been very definitely hampered
by a kind of apriorism with which these problems are generally
approached. In particular, the empiricist assumptions that have
dominated the study of acquisition of knowledge for many years
seem to me to have been adopted quite without warrant and to have
no special status among the many possibilities that one might
imagine as to how the mind functions.

In this connection, it is illuminating to follow the debate that
has arisen since the views I have just sketched were advanced
a few years ago as a program of research — I should say, since this
position was resurrected, because to a significant extent it is
the traditional rationalist approach, now amplified and sharpened
and made far more explicit in terms of the tentative conclusions
that have been reached in the recent study of linguistic competence.
Two outstanding American philosophers, Nelson Goodman and Hilary
Putnam, have made recent contributions to this discussion — both
misconceived, in my opinion, but instructive in the misconceptions
that they reveal.

Goodman's treatment of the question suffers first from an historical
misunderstanding and second from a failure to formulate correctly
the exact nature of the problem of acquisition of knowledge.
His historical misunderstanding has to do with the issue between
Locke and whomever Locke thought he was criticising in his discussion
of innate ideas. According to Goodman, "Locke made ... acutely
clear" that the doctrine of innate ideas is "false or
meaningless." In fact, however, Locke's critique had little
relevance to any familiar doctrine of the seventeenth century.
The arguments that Locke gave were considered and dealt with
in quite a satisfactory way in the earliest seventeenth-century
discussions of innate ideas, for example those of Lord Herbert
and Descartes, both of whom took for granted that the system of
innate ideas and principles would not function unless appropriate
stimulation took place. For this reason, Locke's arguments, none
of which took cognisance of this condition, are without force;
" for some reason, he avoided the issues that had been discussed
in the preceding half-century. Furthermore, as Leibnitz observed,
Locke's willingness to make use of a principle of "reflection"
makes it almost impossible to distinguish his approach from that
of the rationalists, except for his failure to take even those
steps suggested by his predecessors toward specifying the character
of this principle.

But, historical issues aside, I think that Goodman misconstrues
the substantive problem as well. He argues that first-language
learning poses no real problem, because prior to first-language
learning the child has already acquired the rudiments of a symbolic
system in his ordinary dealings with the environment. Hence,
first-language learning is analogous to second-language learning
in that the fundamental step has already been taken, and details.
can be elaborated within an already existing framework. This
argument might have some force if it were possible to show that
the specific properties of grammar — say, the distinction of deep
and surface structure, the specific properties of grammatical
transformations, the principles of rule ordering, and so on — were
present in some form in these already acquired prelinguistic "symbolic
systems." But since there is not the slightest reason to
believe that this is so, the argument collapses. It is based
on an equivocation similar to that discussed earlier in connection
with the argument that language evolved from animal communication.
In that case, as we observed, the argument turned on a metaphorical
use of the term "language." In Goodman's case, the argument
is based entirely on a vague use of the term "symbolic system,"
and it collapses as soon as we attempt to give this term a precise
meaning. If it were possible to show that these prelinguistic
symbolic systems share certain significant properties with natural
language, we could then argue that these properties of natural
language are acquired by analogy. Of course, we would then face
the problem of explaining how the prelinguistic symbolic systems
developed these properties. But since no one has succeeded in
showing that the fundamental properties of natural language — those
discussed in Lecture 2, for example — appear in prelinguistic symbolic
systems or any others, the latter problem does not arise.

According to Goodman, the reason why the problem of second-language
learning is different from that of first-language learning is
that "once one language is available," it "can
be used for giving explanation and instruction." He then
goes on to argue that "acquisition of an initial language
is acquisition of a secondary symbolic system" and is quite
on a par with normal second-language acquisition. The primary
symbolic systems to which he refers are "rudimentary-prelinguistic
symbolic systems in which gestures and sensory and perceptual
occurrences of all sorts function as signs." But evidently
these prelinguistic symbolic systems cannot be "used for
giving explanation and instruction" in the way a first language
can be used in second-language instruction. Therefore, even on
his own grounds, Goodman's argument is incoherent.

Goodman maintains that "the claim we are discussing cannot
be experimentally tested even when we have an acknowledged example
of a 'bad' language" and that "the claim has not even
been formulated to the extent of citation of a single general
property of 'bad' languages." The first of these conclusions
is correct, in his sense of "experimental test," namely
a test in which we "take an infant at birth, isolate it from
all the influences of our language-bound culture, and attempt
to inculcate it with one of the 'bad' artificial languages."
Obviously this is not feasible. But there is no reason why we
should be dismayed by the impossibility of carrying out such a
test as this. There are many other ways, for example, those discussed
in Lecture 2 and the references cited there — in which evidence
can be obtained concerning the properties of grammars and conclusions
regarding the general properties of such grammars can be put to
empirical test. Any such conclusion immediately specifies, correctly
or incorrectly, certain properties of "bad" languages.
Since there are dozens of papers and books that attempt to formulate
such properties, his second claim, that not "a single general
property of 'bad' languages" has been formulated, is rather
surprising. One might try to show that these attempts are misguided
or questionable, but one can hardly maintain seriously that they
do not exist. Any formulation of a principle of universal grammar
makes a strong empirical claim, which can be falsified by finding
counter-instances in some human language, along the lines of the
discussion in Lecture 2. In linguistics, as in any other field,
it is only in such indirect ways as this that one can hope to
find evidence bearing on non-trivial hypotheses. Direct experimental
tests of the sort that Goodman mentions are rarely possible, a
matter that may be unfortunate but is nevertheless characteristic
of most research.

At one point Goodman remarks, correctly, that even though "for
certain remarkable facts I have no alternative explanation ...
that alone does not dictate acceptance of whatever theory may
be offered; for the theory might be worse than none. Inability
to explain a fact does not condemn me to accept an intrinsically
repugnant and incomprehensible theory." But now consider
the theory of innate ideas that Goodman regards as "intrinsically
repugnant and incomprehensible." Notice, first, that the
theory is obviously not "incomprehensible," on his terms.
Thus he appears to be willing, in this article, to accept the
view that in some sense the mature mind contains ideas; it is
obviously not "incomprehensible," then, that some of
these ideas are "implanted in the mind as original equipment,"
to use his phraseology. And if we turn to the actual doctrine
as developed in rationalist philosophy, rather than Locke's caricature,
the theory becomes even more obviously comprehensible. There
is nothing incomprehensible in the view that stimulation provides
the occasion for the mind to apply certain innate interpretive
principles, certain concepts that proceed from "the power
of understanding" itself, from the faculty of thinking rather
than from external objects directly. To take an example from
Descartes (Reply to Objections, V):

When first in infancy we see a triangular figure depicted on paper,
this figure cannot show us how a real triangle ought to be conceived
in the way in which geometricians consider it, because the true
triangle is contained in this figure, just as the statue of Mercury
is contained in a rough block of wood. But because we already
possess within us the idea of a true triangle, and it can be more
easily conceived by our mind than the more complex figure of the
triangle drawn on paper, we, therefore, when we see the composite
figure, apprehend not it itself, but rather the authentic triangle.

In this sense the idea of a triangle is innate. Surely the notion
is comprehensible; there would be no difficulty, for example,
in programming a computer to react to stimuli along these lines
(though this would not satisfy Descartes, for other reasons).
Similarly, there is no difficulty in principle in programming
a computer with a schematism that sharply restricts the form of
a generative grammar, with an evaluation procedure for grammars
of the given form, with a technique for determining whether given
data are compatible with a grammar of the given form, with a fixed
substructure of entities (such as distinctive features), rules,
and principles, and so on — in short, with a universal grammar of
the sort that has been proposed in recent years. For reasons
that I have already mentioned, I believe that these proposals
can be properly regarded as a further development of classical
rationalist doctrine, as an elaboration of some of its main ideas
regarding language and mind. Of course, such a theory will be
"repugnant" to one who accepts empiricist doctrine and
regards it as immune to question or challenge. It seems to me
that this is the heart of the matter.

Putnam's paper deals more directly with the points at issue, but
it seems to me that his arguments are also inconclusive, because
of certain incorrect assumptions that he makes about the nature
of the acquired grammars. Putnam assumes that on the level of
phonetics the only property proposed in universal grammar is that
a language has "a short list of phonemes." This, he
argues, is not a similarity among languages that requires elaborate
explanatory hypotheses. The conclusion is correct; the assumption
is quite wrong. In fact, as I have now pointed out several times,
very strong empirical hypotheses have been proposed regarding
the specific choice of universal features, conditions on the form
and organisation of phonological rules, conditions on rule application,
and so on. If these proposals are correct or near correct, then
"similarities among languages" at the level of sound
structure are indeed remarkable and cannot be accounted for simply
by assumptions about memory capacity, as Putnam suggests.

Above the level of sound structure, Putnam assumes that the only
significant properties of language are that they have proper names,
that the grammar contains a phrase structure component, and that
there are rules "abbreviating" sentences generated by
the phrase structure component. He argues that the nature of
the phrase structure component is determined by the existence
of proper names; that the existence of a phrase structure component
is explained by the fact that "all the natural measures of
complexity c.f. an algorithm — size of the machine table, length
of computations, time, and space required for the computation
— lead to the . . . result"; that phrase structure systems
provide the "algorithms which are 'simplest' for virtually
any computing system," hence also "for naturally evolved
'computing systems' "; and that there is nothing surprising
in the fact that languages contain rules of abbreviation.

Each of the three conclusions involves a false assumption. From
the fact that a phrase structure system contains proper names
one can conclude almost nothing about its other categories. In
fact, there is much dispute at the moment about the general properties
of the underlying phrase structure system for natural languages;
the dispute is not in the least resolved by the existence of proper
names.

As to the second point, it is simply untrue that all measures
of complexity and speed of computation lead to phrase structure
rules as the "simplest possible algorithm." The only
existing results that are even indirectly relevant show that context-free
phrase structure grammars (a reasonable model for rules generating
deep structures, when we exclude the lexical items and the distributional
conditions they meet) receive an automata-theoretic interpretation
as non-deterministic push-down storage automata, but the latter
is hardly a "natural" notion from the point of view
of "simplicity of algorithms" and so forth. In fact,
it can be argued that the somewhat similar but not formally related
concept of real-time deterministic automation is far more "natural"
in terms of time and space conditions on computation.

However, it is pointless to pursue this topic, because what is
at stake is not the "simplicity" of phrase structure
grammars but rather of transformational grammars with a phrase
structure component that plays a role in generating deep structures.
And there is absolutely no mathematical concept of "ease
of computation" or "simplicity of algorithm" that
even vaguely suggests that such systems may have some advantage
over the kinds of automata that have been seriously investigated
from this point of view — for example, finite state automata, linear
bounded automata, and so on. The basic concept of "structure-dependent
operation" has never even been considered in a strictly mathematical
concept. The source of this confusion is a misconception on Putnam's
part as to the nature of grammatical transformations. They are
not rules that "abbreviate" sentences; rather, they
are operations that form surface structures from underlying deep
structures, in such ways as are illustrated in the preceding lecture
and the references there cited." Hence, to show that transformational
grammars are the "simplest possible" one would have
to demonstrate that the "optimal" computing system would
take a string of symbols as input and determine its surface structure,
its underlying deep structure, and the sequence of transformational
operations that relates them. Nothing of the sort has been shown;
in fact, the question has never even been raised.

Putnam argues that even if significant uniformities among languages
were to be discovered, there would be a simpler explanation than
the hypothesis of an innate universal grammar, namely their common
origin. But this proposal involves a serious misunderstanding
of the problem at issue. The grammar of a language must be discovered
by the child from the data presented to him. As noted earlier,
the empirical problem is to find a hypothesis about initial structure
rich enough to account for the fact that a specific grammar is
constructed by the child, but not so rich as to be falsified by
the known diversity of language.

Questions of common origin are of potential relevance to this
empirical issue in only one respect: If the existing languages
are not a "fair sample" of the "possible languages,"
we may be led mistakenly to propose too narrow a schema for universal
grammar. However, as I mentioned earlier, the empirical problem
that we face today is that no one has been able to devise an initial
hypothesis rich enough to account for the acquisition by the child
of the grammar that we are, apparently, led to attribute to him
when we try to account for his ability to use the language in
the normal way. The assumption of common origin contributes nothing
to explaining how this achievement is possible. In short, the
language is "reinvented" each time it is learned, and
the empirical problem to be faced by the theory of learning is
how this invention of grammar can take place.

Putnam does face this problem and suggests that there might be
"general multipurpose learning strategies" that account
for this achievement. It is, of course, an empirical question
whether the properties of the "language faculty" are
specific to language or are merely a particular case of much more
general mental faculties (or learning strategies).

This is a problem that has been discussed earlier in this lecture,
inconclusively and in a slightly different context. Putnam takes
for granted that it is only general "learning strategies"
that are innate but suggests no grounds for this empirical assumption.
As I have argued earlier, a non-dogmatic approach to this problem
can be pursued, without reliance on unargued assumptions of this
sort — that is, through the investigation of specific areas of human
competence, such as language, followed by the attempt to devise
a hypothesis that will account for the development of this competence.
If we discover through such investigation that the same "learning
strategies" are sufficient to account for the development
of competence in various domains, we will have reason to believe
that Putnam's assumption is correct. If we discover that the
postulated innate structures differ from case to case, the only
rational conclusion would be that a model of mind must involve
separate "faculties," with unique or partially unique
properties. I cannot see how anyone can resolutely insist on
one or the other conclusion in the light of the evidence now available
to us. But one thing is quite clear: Putnam has no justification
for his final conclusion, that "invoking 'Innateness' only
postpones the problem of learning; it does not solve it."
Invoking an innate representation of universal grammar does solve
the problem of learning, if it is true that this is the basis
for language acquisition, as it well may be. If, on the other
hand, there are general learning strategies that account for the
acquisition of grammatical knowledge, then postulation of an innate
universal grammar will not "postpone" the problem of
learning, but will rather offer an incorrect solution to this
problem. The issue is an empirical one of truth or falsity, not
a methodological one of states of investigation.

To summarise, it seems to me that neither Goodman nor Putnam offers
a serious counterargument to the proposals concerning innate mental
structure that have been advanced (tentatively, of course, as
befits empirical hypotheses) or suggests a plausible alternative
approach, with empirical content, to the problem of acquisition
of knowledge.

Assuming the rough accuracy of conclusions that seem tenable today,
it is reasonable to suppose that a generative grammar is a system
of many hundreds of rules of several different types, organised
in accordance with certain fixed principles of ordering and applicability
and containing a certain fixed substructure which, along with
the general principles of organisation, is common to all languages.
There is no a priori "naturalness" to such a system,
any more than there is to the detailed structure of the visual
cortex. No one who has given any serious thought to the problem
of formalising inductive procedures or "heuristic methods"
is likely to set much store by the hope that such a system as
a generative grammar can be constructed by methods of any generality.

To my knowledge, the only substantive proposal to deal with the
problem of acquisition of knowledge of language is the rationalist
conception that I have outlined. To repeat: Suppose that we assign
to the mind, as an innate property, the general theory of language
that we have called "universal grammar." This theory
encompasses the principles that I discussed in the preceding lecture
and many others of the same sort, and it specifies a certain subsystem
of rules that provides a skeletal structure for any language and
a variety of conditions, formal and substantive, that any further
elaboration of the grammar must meet. The theory of universal
grammar, then, provides a schema to which any particular grammar
must conform. Suppose, furthermore, that we can make this schema
sufficiently restrictive so that very few possible grammars conforming
to the schema will be consistent with the meagre and degenerate
data actually available to the language learner. His task, then,
is to search among the possible grammars and select one that is
not definitely rejected by the data available to him. What faces
the language learner, under these assumptions, is not the impossible
task of inventing a highly abstract and intricately structured
theory on the basis of degenerate data, but rather the much more
manageable task of determining whether these data belong to one
or another of a fairly restricted set of potential languages.

The tasks of the psychologist, then, divide into several sub-tasks.
The first is to discover the innate schema that characterises
the class of potential languages — that defines the "essence"
of human language. This sub-task falls to that branch of human
psychology known as linguistics; it is the problem of traditional
universal grammar, of contemporary linguistic theory. The second
sub-task is the detailed study of the actual character of the
stimulation and the organism-environment interaction that sets
the innate cognitive mechanism into operation. This is a study
now being undertaken by a few psychologists, and it is particularly
active right here in Berkeley. It has already led to interesting
and suggestive conclusions. One might hope that such study will
reveal a succession of maturational stages leading finally to
a full generative grammar.

A third task is that of determining just what it means for a hypothesis
about the generative grammar of a language to be "consistent"
with the data of sense. Notice that it is a great oversimplification
to suppose that a child must discover a generative grammar that
accounts for all the linguistic data that has been presented to
him and that "projects" such data to an infinite range
of potential sound-meaning relations. In addition to achieving
this, he must also differentiate the data of sense into those
utterances that give direct evidence as to the character of the
underlying grammar and those that must be rejected by the hypothesis
he selects as ill-formed, deviant, fragmentary, and so on. Clearly,
everyone succeeds in carrying out this task of differentiation — we
all know, within tolerable limits of consistency, which sentences
are well formed and literally interpretable, and which must be
interpreted as metaphorical, fragmentary, and deviant along many
possible dimensions. I doubt that it has been fully appreciated
to what extent this complicates the problem of accounting for
language acquisition. Formally speaking, the learner must select
a hypothesis regarding the language to which he is exposed that
rejects a good part of the data on which this hypothesis must
rest. Again, it is reasonable to suppose this is possible only
if the range of tenable hypotheses is quite limited — if the innate
schema of universal grammar is highly restrictive. The third
sub-task, then, is to study what we might think of as the problem
of "confirmation" — in this context, the problem of what
relation must hold between a potential grammar and a set of data
for this grammar to be confirmed as the actual theory of the language
in question.

I have been describing the problem of acquisition of knowledge
of language in terms that are more familiar in an epistemological
than a psychological context, but I think that this is quite appropriate.
Formally speaking, acquisition of "common-sense knowledge"
— knowledge of a language, for example — is not unlike theory construction
of the most abstract sort. Speculating about the future development
of the subject, it seems to me not unlikely, for the reasons I
have mentioned, that learning theory will progress by establishing
the innately determined set of possible hypotheses, determining
the conditions of interaction that lead the mind to put forth
hypotheses from this set, and fixing the conditions under which
such a hypothesis is confirmed — and, perhaps, under which much
of the data is rejected as irrelevant for one reason or another.

Such a way of describing the situation should not be too surprising
to those familiar with the history of psychology at Berkeley,
where, after all, Edward Tolman has given his name to the psychology
building; but I want to stress that the hypotheses I am discussing
are qualitatively different in complexity and intricacy from anything
that was considered in the classical discussions of learning.
As I have now emphasised several times, there seems to be little
useful analogy between the theory of grammar that a person has
internalised and that provides the basis for his normal, creative
use of language, and any other cognitive system that has so far
been isolated and described; Similarly, there is little useful
analogy between the schema of universal grammar that we must,
I believe, assign to the mind as an innate character, and any
other known system of mental organisation. It is quite possible
that the lack of analogy testifies to our ignorance of other aspects
of mental function, rather than to the absolute uniqueness of
linguistic structure; but the fact is that we have, for the moment,
no objective reason for supposing this to be true.

The way in which I have been describing acquisition of knowledge
of language calls to mind a very interesting and rather neglected
lecture given by
Charles Sanders Peirce more than fifty years
ago, in which he developed some rather similar notions about acquisition
of knowledge in general. Peirce argued that the general
limits of human intelligence are much more narrow than might be
suggested by romantic assumptions about the limitless perfectibility
of man (or, for that matter, than are suggested by his own "pragmaticist"
conceptions of the course of scientific progress in his better-known
philosophical studies). He held that innate limitations on admissible
hypotheses are a precondition for successful theory construction,
and that the "guessing instinct" that provides hypotheses
makes use of inductive procedures only for "corrective action,"
Peirce maintained in this lecture that the history of early science
shows that something approximating a correct theory was discovered
with remarkable ease and rapidity, on the basis of highly inadequate
data, as soon as certain problems were faced; he noted "how
few were the guesses that men of surpassing genius had to make
before they rightly guessed the laws of nature." And, he
asked, "How was it that man was ever led to entertain that
true theory? You cannot say that it happened by chance, because
the chances are too overwhelmingly against the single true theory
in the twenty or thirty thousand years during which man has been
a thinking animal, ever having come into any man's head."
A fortiori, the chances are even more overwhelmingly against
the true theory of each language ever having come into the head
of every four-year-old child. Continuing with Peirce: "Man's
mind has a natural adaptation to imagining correct theories of
some kinds.... If man had not the gift of a mind adapted to his
requirements, he could not have acquired any knowledge."
Correspondingly, in our present case, it seems that knowledge
of a languages grammar — can be acquired only by an organism that
is "preset" with a severe restriction on the form of
grammar. This innate restriction is a precondition, in the Kantian
sense, for linguistic experience, and it appears to be the critical
factor in determining the course and result of language learning.
The child cannot know at birth which language he is to learn,
but he must know that its grammar must be of a predetermined
form that excludes many imaginable languages. Having selected
a permissible hypothesis, he can use inductive evidence for corrective
action, confirming or disconfirming his choice. Once the hypothesis
is sufficiently well confirmed, the child knows the language defined
by this hypothesis; consequently, his knowledge extends enormously
beyond his experience and, in fact, leads him to characterise
much of the data of experience as defective and deviant.

Peirce regarded inductive processes as rather marginal to the
acquisition of knowledge; in his words, "Induction has no
originality in it, but only tests a suggestion already made."
To understand how knowledge is acquired, in the rationalist view
that Peirce outlined, we must penetrate the mysteries of what
he called "abduction," and we must discover that which
"gives a rule to abduction and so puts a limit upon admissible
hypotheses." Peirce maintained that the search for principles
of abduction leads us to the study of innate ideas, which provide
the instinctive structure of human intelligence. But Peirce was
no dualist in the Cartesian sense; he argued (not very persuasively,
in my opinion) that there is a significant analogy between human
intelligence, with its abductive restrictions, and animal instinct.
Thus, he maintained that man discovered certain true theories
only because his "instincts must have involved from the beginning
certain tendencies to think truly" about certain specific
matters; similarly, "You cannot seriously think that every
little chicken that is hatched, has to rummage through all possible
theories until it lights upon the good idea of picking up something
and eating it. On the contrary, you think that the chicken has
an innate idea of doing this; that is to say, that it can think
of this, but has no faculty of thinking anything else.... But
if you are going to think every poor chicken endowed with an innate
tendency towards a positive truth, why should you think to man
alone this gift is denied?"

No one took up Peirce's challenge to develop a theory of abduction,
to determine those principles that limit the admissible hypotheses
or present them in a certain order. Even today, this remains
a task for the future. It is a task that need not be undertaken
if empiricist psychological doctrine can be substantiated; therefore,
it is of great importance to subject this doctrine to rational
analysis, as has been done, in part, in the study of language.
I would like to repeat that it was the great merit of structural
linguistics, as of Hullian learning theory in its early stages
and of several other modern developments, to have given precise
form to certain empiricist assumptions." Where this step
has been taken, the inadequacy of the postulated mechanisms has
been clearly demonstrated, and, in the case of language at least,
we can even begin to see just why any methods of this sort must
fail — for example, because they cannot, in principle, provide for
the properties of deep structures and the abstract operations
of formal grammar. Speculating about the future, I think it is
not unlikely that the dogmatic character of the general empiricist
framework and its inadequacy to human and animal intelligence
will gradually become more evident as specific realisations, such
as taxonomic linguistics, behaviourist learning theory, and the
perception models," heuristic methods, and "general
problem solvers" of the early enthusiasts of "artificial
intelligence," are successively rejected on empirical grounds
when they are made precise and on grounds of vacuity when they
are left vague. And — assuming this projection to be accurate — it
will then be possible to undertake a general study of the limits
and capacities of human intelligence, to develop a Peircean logic
of abduction.

Modern psychology is not devoid of such initiatives. The contemporary
study of generative grammar and its universal substructure and
governing principles is one such manifestation. Closely related
is the study of the biological bases of human language, an investigation
to which Eric Lenneberg has made substantial contributions."
It is tempting to see a parallel development in the very important
work of Piaget and others interested in "genetic epistemology,"
but I am not sure that this is accurate. It is not clear to me,
for example, what Piaget takes to be the basis for the transition
from one of the stages that he discusses to the next, higher stage.
There is, furthermore, a possibility, suggested by recent work
of Mehler and Bever," that the deservedly well-known results
on conservation, in particular, may not demonstrate successive
stages of intellectual development in the sense discussed by Piaget
and his coworkers, but something rather different. If the preliminary
results of Mehler and Bever are correct, then it would follow
that the "final stage," in which conservation is properly
understood, was already realised at a very early period of development.
Later, the child develops a heuristic technique that is largely
adequate but that fails under the conditions of the conservation
experiment. Still later, he adjusts this technique successfully
and once again makes the correct judgments in the conservation
experiment. If this analysis is correct, then what we are observing
is not a succession of stages of intellectual development, in
Piaget's sense, but rather slow progress in bringing heuristic
techniques into line with general concepts that have always been
present. These are interesting alternatives; either way, the
results may bear in important ways on the topics we are considering.

Still more clearly to the point, I think, are the developments
in comparative ethology over the past thirty years, and certain
current work in experimental and physiological psychology. One
can cite many examples: for example, in the latter category, the
work of Bower, suggesting an innate basis for the perceptual
constancies; studies in the Wisconsin primate laboratory on complex
innate releasing mechanisms in rhesus monkeys; the work of Hubel,
Barlow, and others on highly specific analysing mechanisms in
the lower cortical centers of mammals; and a number of comparable
studies of lower organisms (for example, the beautiful work of
Lettvin and his associates on frog vision). There is now good
evidence from such investigations that perception of line, angle,
motion, and other complex properties of the physical world is
based on innate organisation of the neural system.

In some cases at least, these built-in structures will degenerate
unless appropriate stimulation takes place at an early stage in
life, but although such experience is necessary to permit the
innate mechanisms to function, there is no reason to believe that
it has more than a marginal effect on determining how they function
to organise experience. Furthermore, there is nothing to suggest
that what has so far been discovered is anywhere near the limit
of complexity of innate structures. The basic techniques for
exploring the neural mechanisms are only a few years old, and
it is impossible to predict what order of specificity and complexity
will be demonstrated when they come to be extensively applied.
For the present, it seems that most complex organisms have highly
specific forms of sensory and perceptual organisation that are
associated with the Umwelt and the manner of life of the
organism. There is little reason to doubt that what is true of
lower organisms is true of humans as well. Particularly in the
case of language, it is natural to expect a close relation between
innate properties of the mind and features of linguistic structure;
for language, after all, has no existence apart from its mental
representation. Whatever properties it has must be those that
are given to it by the innate mental processes of the organism
that has invented it and that invents it anew with each succeeding
generation, along with whatever properties are associated with
the conditions of its use. Once again, it seems that language
should be, for this reason, a most illuminating probe with which
to explore the organisation of mental processes.

Turning to comparative ethology, it is interesting to note that
one of its earliest motivations was the hope that through the
"investigation of the a priori, of the innate working hypotheses
present in subhuman organisms," it would be possible to shed
light on the a priori forms of human thought. This formulation
of intent is quoted from an early and little-known paper by Konrad
Lorenz." Lorenz goes on to express views very much like those
Peirce had expressed a generation earlier. He maintains:

One familiar with the innate modes of reaction of subhuman organisms
can readily hypothesise that the a priori is due to hereditary
differentiations of the central nervous system which have become
characteristic of the species, producing hereditary dispositions
to think in certain forms.... Most certainly Hume was wrong when
he wanted to derive all that is a priori from that which the senses
supply to experience, just as wrong as Wundt or Helmholtz who
simply explain it as an abstraction from preceding experience.
Adaptation of the a priori to the real world has no more originated
from "experience" than adaptation of the fin of the
fish to the properties of water. just as the form of the fin is
given a priori, prior to any individual negotiation of the young
fish with the water, and just as it is this form that makes possible
this negotiation, so it is also the case with our forms of perception
and categories in their relationship to our negotiation with the
real external world through experience. In the case of animals,
we find limitations specific to the forms of experience possible
for them. We believe we can demonstrate the closest functional
and probably genetic relationship between these animal a priori's
and our human a priori. Contrary to Hume, we believe, just as
did Kant, that a "pure" science of innate forms of human
thought, independent of all experience, is possible.

Peirce, to my knowledge, is original and unique in stressing
the problem of studying the rules that limit the class of possible
theories. Of course, his concept of abduction, like Lorenz's
biological a priori, has a strongly Kantian flavour, and all derive
from the rationalist psychology that concerned itself with the
forms, the limits, and the principles that provide "the sinews
and connections" for human thought, that underlie "that
infinite amount of knowledge of which we are not always conscious,"
of which Leibnitz spoke. It is therefore quite natural that we
should link these developments to the revival of philosophical
grammar, which grew from the same soil as an attempt, quite fruitful
and legitimate, to explore one basic facet of human intelligence.

In recent discussion, models and observations derived from ethology
have frequently been cited as providing biological support, or
at least analogue, to new approaches to the study of human intelligence.
I cite these comments of Lorenz's mainly in order to show that
this reference does not distort the outlook of at least some of
the founders of this domain of comparative psychology.

One word of caution is necessary in referring to Lorenz, now that
he has been discovered by Robert Ardrey and Joseph Alsop and popularised
as a prophet of doom. It seems to me that Lorenz's views on human
aggression have been extended to near absurdity by some of his
expositors. It is no doubt true that there are innate tendencies
in the human psychic constitution that lead to aggressiveness
under specific social and cultural conditions. But there is little
reason to suppose that these tendencies are so dominant as to
leave us forever tottering on the brink of a Hobbesian war of
all against all — as, incidentally, Lorenz at least is fully aware,
if I read him rightly. Scepticism is certainly in order when
a doctrine of man's "inherent aggressiveness" comes
to the surface in a society that glorifies competitiveness, in
a civilisation that has been distinguished by the brutality of
the attack that it has mounted against less fortunate peoples.
It is fair to ask to what extent the enthusiasm for this curious
view of man's nature is attributable to fact and logic and to
what extent it merely reflects the limited extent to which the
general cultural level has advanced since the days when Clive
and the Portuguese explorers taught the meaning of true savagery
to the inferior races that stood in their way.

In any event, I would not want what I am saying to be confused
with other, entirely different attempts to revive a theory of
human instinct. What seems to me important in ethology is its
attempt to explore the innate properties that determine how knowledge
is acquired and the character of this knowledge. Returning to
this theme, we must consider a further question: How did the human
mind come to acquire the innate structure that we are led to attribute
to it? Not too surprisingly, Lorenz takes the position that this
is simply a matter of natural selection. Peirce offers a rather
different speculation, arguing that "nature fecundates the
mind of man with ideas which, when these ideas grow up, will resemble
their father, Nature." Man is "provided with certain
natural beliefs that are true" because "certain uniformities
... prevail throughout the universe, and the reasoning mind is
[it]self a product of this universe. These same laws are thus,
by logical necessity, incorporated in his own being." Here,
it seems clear that Peirce's argument is entirely without force
and that it offers little improvement over the pre-established
harmony that it was presumably intended to replace. The fact
that the mind is a product of natural laws does not imply that
it is equipped to understand these laws or to arrive at them by
"abduction." There would be no difficulty in designing
a device (say, programming a computer) that is a product of natural
law, but that, given data, will arrive at any arbitrary absurd
theory to "explain" these data.

In fact, the processes by which the human mind achieved its present
stage of complexity and its particular form of innate organisation
are a total mystery, as much so as the analogous questions about
the physical or mental organisation of any other complex organism.
It is perfectly safe to attribute this development to "natural
selection," so long as we realise that there is no substance
to this assertion, that it amounts to nothing more than a belief
that there is some naturalistic explanation for these phenomena.
The problem of accounting for evolutionary development is, in
some ways, rather like that of explaining successful abduction.
The laws that determine possible successful mutation and the
nature of complex organisms are as unknown as the laws that determine
the choice of hypotheses." With no knowledge of the laws
that determine the organisation and structure of complex biological
systems, it is just as senseless to ask what the "probability"
is for the human mind to have reached its present state as it
is to inquire into the "probability" that a particular
physical theory will be devised. And, as we have noted, it is
idle to speculate about laws of learning until we have some indication
of what kind of knowledge is attainable — in the case of language,
some indication of the constraints on the set of potential grammars.

In studying the evolution of mind, we cannot guess to what extent
there are physically possible alternatives to, say, transformational
generative grammar, for an organism meeting certain other physical
conditions characteristic of humans. Conceivably, there are none — or
very few in which case talk about evolution of the language capacity
is beside the point. The vacuity of such speculation, however,
has no bearing one way or another on those aspects of the problem
of mind that can be sensibly pursued. It seems to me that these
aspects are, for the moment, the problems illustrated in the case
of language by the study of the nature, the use, and the acquisition
of linguistic competence.

There is one final issue that deserves a word of comment. I have
been using mentalistic terminology quite freely, but entirely
without prejudice as to the question of what may be the physical
realisation of the abstract mechanisms postulated to account for
the phenomena of behaviour or the acquisition of knowledge. We
are not constrained, as was Descartes, to postulate a second substance
when we deal with phenomena that are not expressible in terms
of matter in motion, in his sense. Nor is there much point in
pursuing the question of psychophysical parallelism, in this connection.
It is an interesting question whether the functioning and evolution
of human mentality can 'be accommodated within the framework of
physical explanation, as presently conceived, or whether there
are new principles, now unknown, that must be invoked, perhaps
principles that emerge only at higher levels of organisation than
can now be submitted to physical investigation. We can, however,
be fairly sure that there will be a physical explanation for the
phenomena in question, if they can be explained at all, for an
uninteresting terminological reason, namely that the concept of
"physical explanation" will no doubt be extended to
incorporate whatever is discovered in this domain, exactly as
it was extended to accommodate gravitational and electromagnetic
force, massless particles, and numerous other entities and processes
that would have offended the common sense of earlier generations.
But it seems clear that this issue need not delay the study of
the topics that are now open to investigation, and it seems futile
to speculate about matters so remote from present understanding.

I have tried to suggest that the study of language may very well,
as was traditionally supposed, provide a remarkably favourable
perspective for the study of human mental processes. The creative
aspect of language use, when investigated with care and respect
for the facts, shows that current notions of habit and generalisation,
as determinants of behaviour or knowledge, are quite inadequate.
The abstractness of linguistic structure reinforces this conclusion,
and it suggests further that in both perception and learning the
mind plays an active role in determining the character of the
acquired knowledge. The empirical study of linguistic universals
has led to the formulation of highly restrictive and, I believe,
quite plausible hypotheses concerning the possible variety of
human languages, hypotheses that contribute to the attempt to
develop a theory of acquisition of knowledge that gives due place
to intrinsic mental activity. It seems to me, then, that the
study of language should occupy a central place in general psychology.

Surely the classical questions of language and mind receive no
final solution, or even the hint of a final solution, from the
work that is being actively pursued today. Nevertheless, these
problems can be formulated in new ways and seen in a new light.
For the first time in many years, it seems to me, there is some
real opportunity for substantial progress in the study of the
contribution of the mind to perception and the innate basis for
acquisition of knowledge. Still, in many respects, we have not
made the first approach to a real answer to the classical problems.
For example, the central problems relating to the creative aspect
of language use remain as inaccessible as they have always been.
And the study of universal semantics, surely crucial to the full
investigation of language structure, has barely advanced since
the medieval period. Many other critical areas might be mentioned
where progress has been slow or nonexistent. Real progress has
been made in the study of the mechanisms of language, the formal
principles that make possible the creative aspect of language
use and that determine the phonetic form and semantic content
of utterances. Our understanding of these mechanisms, though
only fragmentary, does seem to me to have real implications for
the study of human psychology. By pursuing the kinds of research
that now seem feasible and by focusing attention on certain problems
that are now accessible to study, we may be able to spell out
in some detail the elaborate and abstract computations that determine,
in part, the nature of percepts and the character of the knowledge
that we can acquire the highly specific ways of interpreting phenomena
that are, in large measure, beyond our consciousness and control
and that may be unique to man.